Apple Inc.'s new iPhone 6 will go on sale in China on Oct. 17 after winning final approval from regulators who scrutinized the device's security features amid rising concerns in the country about privacy.

The move will bring the iPhone 6 and the big-screen iPhone 6 Plus to China roughly one month after they went on sale in the U.S. and other countries. Apple is counting on the devices to help push deeper in China, the world's largest smartphone market but an increasingly tough battleground for both foreign and domestic companies.